1. Field of the Invention
Coke ovens and the like comprise the general field of invention; however, improvements in pusher ram construction for use in such ovens is the principal matter of interest herein.
2. Description of the Prior Art
Many pusher ram constructions for coke ovens have evolved over the years, particularly in the last few decades of increasing damand for coke for use in steelmaking. Although the general appearance and function of the many pusher rams developed over recent years has not changed too dramatically, one consideration that should always be uppermost in the set of parameters for any new pusher ram design is ram life. No matter how well a pusher ram is designed to do its job, its life span should always be such that it economically justifies the anticipated improvements from the new design. In particular, it should be apparent that achieving significant improvements in the day to day operational and functional performance of a new ram design, when also coupled with increased ram life, comprises the ultimate in improvements in coke oven pusher ram construction. It is these desiderata to which the present improvements are directed.
Typical examples of various prior art pusher ram designs may be found in U.S. Pat. Nos. 2,165,141; 3,272,356; 3,784,034; 3,912,091 and 4,253,915.
The particular prior art pusher ram construction to which the present improvements are directed is one that applicant's assignee has successfully manufactured and marketed in recent years. However, it will be apparent to those skilled in the art, from that which follows, that the developments disclosed herein may readily find general use in other and different ram constructions than that specifically forming the disclosed basis for the present improvements.
In the prior art pusher ram construction referred to above, upon critical analysis and after extensive experience in actual coke production, it has been found that a number of improvements related to accelerated fatigue and heat creep problems are possible that could extend the projected service life of the pusher ram by as much as 20 to 40%. In a typical ram installation where average pusher ram life to service half of a 79 oven battery has been determined to be in excess of five years, this could mean at least an extra two years of use. Moreover, maintenance time and materials, as well as maintenance costs, shoud be diminished over ram life. In addition, improved ram performance and ram life carries with it the additional benefits of maximizing oven usage and efficiency.